Needle-supporting mechanism for pile fabric-producing circular knitting machines

ABSTRACT

Needles are supported by a needle-supporting means closely adjacent to the sinkers against bending in response to pull of pile loop yarn during sinker retraction. When the sinkers are integral with a pivotable lever, an arcuate lever surface concentric with the lever pivot is engageable by an intermediate guide which also engages a portion of the reciprocable needle stems to deter bending of the needles. The needle-supporting ring adjacent to the sinkers may have deep notches forming guideways for swinging portions of the sinker levers. Sinkers translated linearly by a pivotable lever engaging a sinker plate ear are separated by radial partitions carried by the needle cylinder. Such partitions have upper edge slots adjacent to upper ends of the needle stems to receive a complementally slotted needle stem bearing ring. The needle-supporting ring may be segmented.

ilnited States Patent [191 Suppe 1 Oct. 21, 1975 NEEDLE-SUPPORTING MECHANISM FOR PILE FABRIC-PRODUCING CIRCULAR KNITTING MACHINES [75] Inventor: Hansjoachim Suppe,Ingolstadt,

Germany 22 Filed: Sept. 1, 1972 21 Appl. No: 285,676

[30] Foreign Application Priority Data FOREIGN PATENTS OR APPLICATIONS 2,047,401 3/1972 Germany 66/106 7/1970 Germany 66/9 R 5/1908 United Kingdom 66/91 Primary Examiner-W. C. Reynolds Assistant Examiner-Andrew M. Falik Attorney, Agent, or Firm-Robert W. Beach; R. M. Van Winkle [57] ABSTRACT Needles are supported by a needle-supporting means closely adjacent to the sinkers against bending in response to pull of pile loop yarn during sinker retraction. When the sinkers are integral with a pivotable lever, an arcuate lever surface concentric with the lever pivot is engageable by an intermediate guide which also engages a portion of the reciprocable needle stems to deter bending of the needles. The needlesupporting ring adjacent to the sinkers may have deep notches forming guideways for swinging portions of the sinker levers. Sinkers translated linearly by a pivotable lever engaging a sinker plate ear are separated by radial partitions carried by the needle cylinder. Such partitions have upper edge slots adjacent to upper ends of the needle stems to receive a complementally slotted needle stem bearing ring. The needlesupporting ring may be segmented.

4 Claims, 7 Drawing Figures U.S Patent Oct.21, 1975 3 Sheet 1 of6 V 3,913,356

Shee tZ of 6 U.S. Patent Oct. 21, 1975 US. Patent Oct.21,1975 Sheet3of6 3,913,356

Fig. 3

U.S. Patent Oct. 21, 1975 Sheet 4 of6 3,913,356

PRIOR ART Fig. 1.

US. Patent Oct. 21, 1975 Sheet 6 of6 3,913,35

1 NEEDLE-SUPPORTING MECHANISM FOR PILE FABRIC-PRODUCING CIRCULAR KNITTING MACHINES FIELD OF THE INVENTION The invention relates to a circular knitting machine for the production of fabric having pile material interlaced into the knitted mesh fabric base, this machine being equipped with needles which are individually movable between the guide plates of a needle cylinder and with pile loop sinkers which are movable between the needles substantially transversely of the direction of needle movement.

DESCRIPTION OF THE PRIOR ART In circular knitting machines in which the pile loop sinkers are mounted on a stationary fulcrum or swivel axis can be swivelled between the needles such as disclosed in German Pat. application No. P 20 47 401.5, it is necessary to leave unobstructed the space which lies to the outside of the needle ring-to provide clearance for swinging of the pile loop sinkers. Consequently the needles are only supported by a single guide part above the cam elements near the lower parts of the needles. This single guide element lies at the level of the axis about which the pile loop sinkers swing and serves to simultaneously support the needles and the pile loop sinkers.

According to the disclosure of German Pat. application No.21 43 257.5 to which U.S. Pat. No. 3,837,184 corresponds, the pile loop sinkers are reciprocated by two cam elements which operate alternately. One cam element guides a plurality of rocker members, one rocker member being provided for co-operation with each pileloop sinker. The rocker members are capable of swinging about a stationary swivel axis, outside the circle or ring of needles. In the case of this prior proposal, it is, again, necessary to leave unobstructed the region in which the rocker members swivel.

In both of these above-mentioned forms of construction the needles are subject to strong pulling forces in the radially outward direction exerted by the pile material as the pile loop sinkers are retracted. Since the individual needles yield by different amounts to this pulling force, pile loops of different size are formed, with the result that the completed knitted material has a nonuniform appearance. I

SUMMARY OF THE INVENTION According to the invention there is provided a needle support directly in front of the upper portion of the needle stem adjacent to the sinker casting-off level.

This needle support prevents or restrains the needles from being radially outwardly bent at this point and substantially reduces the length of the needle which is .not positively guided. If the pile loop sinkers are rigidly connected to their swinging levers'which are pivotable about a stationary fulcrum or swivel axis, the needle support may be rotatably mounted on a stationary part of the machine, and may compriseguideways or slots into which the levers are swung; Thus, aneedle support of this kind, in addition to supporting the needles, radially guides the pile loop sinker levers. If it is intended that there should be no separate drive for driving the needle supporting ring, then this needle support can be coupled to turn with the needle cylindenthrough the intermediary of the pile loop sinkers. Since different sinkers are in different positions between the extremes of retraction and extension at a given instant in time, a large number of sinker levers are always present in the guide slots. If rectilinearly movable pile loop sinkers are employed, then the needle support may advantageously be mounted in the guideway side plates. Conveniently, the needle support may consist of a plurality of segments, to facilitate accessibility to individual needles and guide plates.

It is a particularly easy matter to exchange these segments if, in the vicinity of each of these segments, each of at least two guide plates has, at its end lying closer to the casting-off or knocking-over plane, a nose which engages over the upper edge of the segment. Each segment has slots in its opposite or lower edge margin corresponding to the locations of these two guide plates. In order to ensure that the segments will also be reliably secured in position in the circumferential direction, it will be found advantageous to provide slots in the upper edge margins of the segments which may partially embrace the noses.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is explained in greater detail below with reference to two embodiments thereof illustrated in the accompanying drawings, which merely show parts of a circular knitting machine in accordance with the invention which are indispensable for understanding of the invention. In the drawings:

FIG. 1 is a radial section through a portion of a circular knitting machine in accordance with the invention, parts being broken away;

FIG. 2 is a radial section through a portion of a circular knitting machine in accordance with a modified form of the invention, with parts broken away;

FIG. 3 is a developed view of a detail of the circular knitting machine illustrated in FIG. 2;

FIG. 4 is a radial section through a prior art machine showing the problem overcome by the present invention;

FIG. 5 is a radial section similar to FIG. 1, but taken along a different portion of the sinker cams showing the sinker in a different operative position;

FIG. 6 is a radial section similar to FIG. 2 but on an enlarged scale showing an auxiliary ring-retaining latch;

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention can be used in different circular knit- "ting machines for the production of fabric with pile material interlaced into a knitted mesh fabric whether the pile material is formed into loops by sinkers swingable on the ends of pivoted levers or by pile loop sinkers movable rectilinearly by engagement with swinging levers. In both cases the region outside the needle ring must be left free to provide clearance for lever swinging.

FIG. 1 illustrates a first embodiment of the invention. Grooves 10 in the lower part of a needle cylinder 1 complementally receive partitions or guide plates 11 which form guideways for the lower portions of cylinder needles 20 and lever-mounted sinkers 2. The cylinder needles 26 are reciprocated in a known manner by engagement of @am elements 30 and 31 with butts 21 of the cylinder needles 20. The cam elements 30 and 31 are carried in a conventional manner by a stationary cam carrier 3. Each pile loop sinker 2 is pivotable about a pivot 22 carried in an annular groove 12 of the needle cylinder 1. Swinging of the pile loop sinkers 2 between the cylinder needles is controlled by means of cam elements 32 and 33 which are attached to the cam carrier 3 and engage complemental portions of the sinker lever. A guide member 34 is located between the cam elements 32 and 33 and is positioned opposite the pivot 22. This guide member 34 serves to guide the swinging movements of the pile loop sinkers by sliding engagement with the accurate lever edge 23, the arc of which is concentric with pivot 22. Further, an upper portion of the outer edge 24 of the needle stem lies in a plane tangential to the portion of edge 23 engaged by tongue 34, so that the cylinder needle 20 also is supported by the guide member 34, with the result that this needle 20 is not shifted by the pulling force exerted by the pile yarn in the direction of the arrow P. As can be seen in FIG. 1, tongue 34 is located a substantial distance above cam ring and, therefore effectively and substantially shortens the portion of the needle length which is subject to bending.

To provide unobstructed swinging clearance of the pile loop sinkers 2, in a circular knitting machine for producing knitted fabric having pile material H enmeshed in the knitted base fabric G, the cylinder needles 20 are not supported in the region between the casting-off plane A and the guide member 34. Consequently, a pulling force exerted in the direction of the arrow P during sinking of pile loops S may cause the cylinder needle 20 to yield or bend, as shown in FIG. 4, particularly if the pile material I-[ is in the form of a pile thread, resulting in a non-uniform pile height and, thus, a non-homogeneous knitted fabric.

To prevent this drawback, a needle support 4 located as near as possible to the casting-off plane A is provided on the side of the cylinder needles 20 remote from the needle cylinder 1. This needle support 4 in the form of an annular ring of T cross section is retained against axial displacement between a shoulder 35 of carrier 3 and a retaining ring 36 attached to the cam carrier 3. The needle engaging tongue of support 4 is equipped with radial guide slots 40, in which the pile loop sinkers 2 are guided during swinging. The tongue end portions between the guide slots 40 extend as far as the upper end 24 of the needle stem, so that they are in a position to prevent the cylinder needles 20 from yielding to the pulling force exerted in the direction of the arrow P.

During formation of the pile loops S, the pile loop sinkers 2 in the guide slots 40 simultaneously carry the needle support 4 with them, so that the needle support 4 rotates synchronously with the needle cylinder 1 relative to the carrier 3, its bearing shoulder 35 and bearing-retaining ring 36. As shown in FIG. 5, an upper portion of the lever of sinker 2 is aligned in a direction perpendicular to the cylinder radius with a wall of the groove 40 of needle support ring 4, so that rotation of the sinker with needle cylinder 1 will cause it to bear against wall 40 and thereby rotate ring 4. When some sinkers are in the position shown in FIG. 1, other sinkers will be in the position of FIG. 5, so that the ring will be subjected to a continuous rotational force and thereby be maintained in a fixed position relative to needles 20. If desired, the needle support 4 could be rotatably mounted instead of on the cam carrier 3 on another stationary machine part. The friction between the needle support 4' and its mounting could be reduced through the use of a roller-bearing ring, instead of having plain bearing engagement with carrier 3 ball bearings or, shoulder 35 and retaining ring 36. Also, if found to be expedient, it is possible to provide a separate drive, such as a chain and sprocket drive, for the needle support 4 to drive it synchronously with the needle cylinder 1. n

FIG. 2 shows another embodiment of the invention, in which pile loop sinkers 5 are reciprocated rectilinearly by two cam elements 50 and 51. The cam element 50 directly engages butts 52 of the pile loop sinkers 5 to effect sinker extension. Cam element 51 acts on one arm of lever 54 to swing the other lever arm engageable with butts 53 of the pile loop sinkers 5 to effect sinker retraction. Details of this sinker extension and retraction mechanism are disclosed in US. Pat. No. 3,837,184. Element 34 is a guide engageable with the arcuate edge of lever 54 to maintain the lever against pivot 22 for smooth controlled swinging of the lever. Unlike guide 34 in FIG. 1, the guide of FIG. 2 does not serve a needle-supporting function. The pile loop sinkers 5 are mounted in a sinker bed 55 and are guided by radial grooves formed in the needle cylinder 1. The sinker bed 55 is mounted on the partitions or guide plates 13 of the needle cylinder 1, and rotation is imparted to this sinker bed 55 by these guide plates 13 in the course of rotation of the latter. The guide plates 13 also carry the pivot 22 on which the rocker members or levers 54 are pivotally mounted. Partitions 13 form guideways for needles 20 and for sinker-retraction levers.

In this embodiment of the invention, the needle support ring 6 is mounted in the upper portions of guide plates 13 at a location such that the needle support ring engages needles 20 closely adjacent to the loop cast-off level A. In this way it is possible to ensure that the needles 20 cannot yield to the pulling force exerted, in the direction of arrow P, by the pile loop sinkers 5 while the latter are forming the required loops in the pile material. Each of the guide plates 13 has a portion above and radially inward relative to pivot 22. Such partition portion has an elongated upper portion closely adjacent to the needle cylinder 1 and extending generally axially alongside the upper end margin of the needle cylinder. The elongated portion projects radially outwardly from the needle cylinderand is joined to a partition portion which projects radially outward relative to the needle cylinder farther than the elongated portion to form a ledge 14. The axially elongated upper portion and ledge 14 thus suggest a stepped configuration. It is preferred that the lower portion of the partition which forms ledge 14 extend upwardly from the ledge so that ledge 14 forms the bottom of a slot, which slot extends parallel to the said upper stem portion 24. The lower margin of the needle supporting ring 6 is received in slots of the partitions and the rings axially lower edge rests on the ledge 14. The guide. plate may include a resilient hook 65 or latch between the needle support 6 and the casting-off plane A to retain the needle support 6 in its correct position against rotational or axial displacement, as shown in FIG. 6, for example. To facilitate replacement of individual partitions 13, the needle support ring 6, instead of being continuous, may consist of mutually overlapping segments 60 and 61, shown in FIG. 3.

FIGS. 3 and 7 illustrate a particularly favourable embodiment of the needle support ring 6, in which the ring includes one or more pairs of segments 60 and 61. The ends of segment 60 are inclined downwardly and inwardly whereas the ends of segment 61 are inclined downwardly and outwardly complementary to the ends of segment 60. Each segment 60 and 61 has, at a distance of a number of needle divisions, two deep notches 62 which are positioned on the side of the segments remote from the casting-off plane A. Each of these notches is located in the vicinity of an associated guide plate 13, and extends parallel to the latter. Each of those guide plates 13 in front of which a notch 62 is located in segment 60 or 61 of the needle support 6 has a nose which engages over the upper edge of the needle support 6 directly above the corresponding notch 62. Segments 60 and 61 are retained in their correct radial position by slots 14 formed in guide plates 13 in which the lower edge margin of the composite ring 6 are received. The axial position of segments 60 and 61 is maintained because their lower edges rest on the bases of the slots 14 and noses 15 on the upper portion of the stepped guide plates 13 project over and engage the upper edges of segments 60 and 61.

In assembling the needle supporting structure, guide plates or partitions 13 having noses 15 are first inserted into position. Segments 61 are then introduced obliquely downwardly into slots 14 of the guide plates 13. The obliquity with which segments 61 are thus inserted into the slots 14 is possible owing to the provision of notches 62 in segments 61. Segments 60 are then thrust into position in a similar manner. The other guide plates 13, which are without noses 15, can now be placed in position, and segments 60 and 61 are secured in their final position by means of the bottoms and sides of slots 14 of these guide plates 13 and noses 15 on the guide plates 13 first inserted.

If a segment 60 or 61 should have to be dismantled, then this is accomplished by carrying out the abovedescribed steps in the reverse sequence. After removal of the few guide plates 13 which are without a nose 15 in the vicinity of the corresponding segment 60 or 61, this segment can be tilted and obliquely upwardly withdrawn. Guide plates 13 having noses 15 can then be taken out.

In order to securely retain segments 60 and 61 in the circumferential direction, further notches 63 may be provided in the upper margins of the segments directly above the notches 62. Notches 62 are significantly wider than guide plates 13. to facilitate exchanging the segments. The width and length of notches 63 correspond to the width and length of the noses 15 and such noses are snugly embraced by the slots to prevent circumferential displacement of the segments. This form of construction for preventing circumferential displacement is particularly advantageous if the segment ends extend of parallel to guide plates 13 instead of being inclined. Any spreading of segments 60 and 61 having upright ends would provide an opening in which a needle stem might lodge. Such upright ends 64 of these segments are shown in dashed line in FIG. 3.

Naturally, the subject matter of the invention could be modified in other ways. For example, segments 60 and 61 could be formed to have a comb-like appearance in plan view, the teeth forming radial slots therebetween. Such slots would form guideways for the levers 54 so that the plates 13 would only connect the sinker bed 55 to the needle cylinder 1. At all events, it is possible, by means of the apparatus proposed according to the invention, to ensure that the pile formed will always be of uniform height. This will be accomplished in a simple manner and irrespective of whether the pile loop sinkers are swung integrally with levers or are driven reciprocably by separate levers.

What we claim is:

1. In a circular knitting machine for producing pile material interlaced into a mesh base including a needle cylinder, individually movable needles having needle stems, and linearly reciprocable sinkers projectible toward the needle cylinder between such needles substantially transversely of the needle lengths and retractable away from the needle cylinder for drawing pile loops and thereby exerting tension on the needles in a direction away from the needle cylinder, driving means for driving the needles and sinkers, the sinkers and needles being synchronously rotatable relative to the driving means, the improvement comprising a segmentedneedle-supporting ring engageable with the sides of the needle stems opposite the needle cylinder at locations closely adjacent to the sinkers.

2. In the circular knitting machine defined in claim 1 further including a sinker bed plate, a plurality of radial partitions connecting the needle cylinder and the sinker bed plate, the needle-supporting ring being carried by the partitions.

3. In a circular knitting machine for producing pile material interlaced into a mesh base including a needle cylinder, individually movable needles having needle stems, a sinker bed plate, a plurality of radial partitions connecting the needle cylinder and the sinker bed plate, and linearly reciprocable sinkers projectible toward the needle cylinder between such needles substantially transversely of the needle lengths and retractable away from the needle cylinder for drawing pile loops and thereby exerting tension on the needles in a direction away from the needle cylinder, driving means for driving the needles and sinkers, the sinkers and needles being synchronously rotatable relative to the driving means, the improvement comprising a needlesupporting ring engageable with the sides of the needle stems opposite the needle cylinder at locations closely adjacent to the sinkers and carried by the partitions, said ring having an axial edge adjacent to the sinkers and an opposite axial edge remote from the sinkers, the partitions being stepped thereby forming an upper portion projecting radially outwardly from the needle cylinder and a lower portion projecting radially outwardly farther from the needle cylinder than said upper portion, said ring axial edge remote from the sinkers being supported on the lower portions of some of the partitions, and others of the partitions having noses projecting from the upper portions thereof and over the needle-supporting ring edge adjacent to the sinkers, said needle-supporting ring including a plurality of axially extending deep notch means in its opposite axial edge for receiving therein the lower portions of the partitions having noses.

4. In the circular knitting machine defined in claim 3, the needle-supporting ring formed by a plurality of individual segments, each of said segments having notches in the axial edge adjacent to the sinkers, said edge engageable by the partition noses, which notches snugly embrace such noses.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent 6 Dated October Zn 107% Inventor(s) Hansjoachim Suppe It is certified that error appears in the above-identified patent Q and that said Letters Patent are hereby corrected as shown below:

Column l, line 18, after "axis" insert -and-.

' Column 2 line 8, cancel the comma after "segments".

Column 3, line 13, cancel "accurate" and insert -arcuate.

Column 4, line 6, cancel "ball bearings or"; line 35, insert 54- before the period.

Column 5, line 52, cancel the period after "13''; line 57,

cancel the clash between "construction" and "for"; line 59, cancel "of" [first instance] a Signed and Sealed thisthirtieth D f March 1976 [SEAL] Arrest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer (omnu'ssiuner ofParents and Trademarks 

1. In a circular knitting machine for producing pile material interlaced into a mesh base including a needle cylinder, individually movable needles having needle stems, and linearly reciprocable sinkers projectible toward the needle cylinder between such needles substantially transversely of the needle lengths and retractable away from the needle cylinder for drawing pile loops and thereby exerting tension on the needles in a direction away from the needle cylinder, driving means for driving the needles and sinkers, the sinkers and needles being synchronously rotatable relative to the driving means, the improvement comprising a segmented needle-supporting ring engageable with the sides of the needle stems opposite the needle cylinder at locations closely adjacent to the sinkers.
 2. In the circular knitting machine defined in claiM 1 further including a sinker bed plate, a plurality of radial partitions connecting the needle cylinder and the sinker bed plate, the needle-supporting ring being carried by the partitions.
 3. In a circular knitting machine for producing pile material interlaced into a mesh base including a needle cylinder, individually movable needles having needle stems, a sinker bed plate, a plurality of radial partitions connecting the needle cylinder and the sinker bed plate, and linearly reciprocable sinkers projectible toward the needle cylinder between such needles substantially transversely of the needle lengths and retractable away from the needle cylinder for drawing pile loops and thereby exerting tension on the needles in a direction away from the needle cylinder, driving means for driving the needles and sinkers, the sinkers and needles being synchronously rotatable relative to the driving means, the improvement comprising a needle-supporting ring engageable with the sides of the needle stems opposite the needle cylinder at locations closely adjacent to the sinkers and carried by the partitions, said ring having an axial edge adjacent to the sinkers and an opposite axial edge remote from the sinkers, the partitions being stepped thereby forming an upper portion projecting radially outwardly from the needle cylinder and a lower portion projecting radially outwardly farther from the needle cylinder than said upper portion, said ring axial edge remote from the sinkers being supported on the lower portions of some of the partitions, and others of the partitions having noses projecting from the upper portions thereof and over the needle-supporting ring edge adjacent to the sinkers, said needle-supporting ring including a plurality of axially extending deep notch means in its opposite axial edge for receiving therein the lower portions of the partitions having noses.
 4. In the circular knitting machine defined in claim 3, the needle-supporting ring formed by a plurality of individual segments, each of said segments having notches in the axial edge adjacent to the sinkers, said edge engageable by the partition noses, which notches snugly embrace such noses. 